Albeet ganswindt



UNITE STATES PATENT OFFICE.

ALBERT GANSIVINDT, OF AIX-LA-OI'IAPELLE, GERMANY, ASSIGNOR TO THE FIRMOF C. II. BOEHRINGER SOIIN, OF NIEDER INGELHEIM, GERMANY.

MORDANTING TEXTIILE FABRIC'S.

SPECIFICATION forming part of Letters Patent No. 568,344, datedSeptember 29, 1896.

Application filed January 29, 1896. Serial No. 577,311. (No specimens.)

To all whom it may concern-- Be it known that I, ALBERT GANSWINDT,doctor of philosophy, chemist, of Aix-la-Chapelle, Prussia, Germany,have invented new and useful Improvements in Dyeing Textile Fabrics orFibers, of which the following is a specification.

This invention relates to dyeing; and it consists, essentially, in theemployment of lactate of zinc as a mordant in dyeing operations.

In mordanting by means of antimony tannin, as usual, the mordantemployedis for the most part unutilized, so that a considerable portionis lostwith the waste waters,

I 5 whereas by the employment of lactate of zinc as a mordant thisdrawback is obviated, because the zinc is almost quantitativelyprecipitated by the fiber, and consequently the quantity of mordantrequired for mordanting a definite quantity of material can be easilydetermined beforehand, thus avoiding loss of useful materials.

In carrying out my process I mordant the material with lactate of zincand subsequently 2 5 dye the material so mordanted. The process may bevariously practiced. For instance, cotton mordanted with lactate of zincmay-be dyed with basic coloring-matters and also some aciddiphenylmethane coloring-matters. Colors produced by these meansare not,however, so fast as colors dyed with tannin and antimony salts, but aresufficiently fast for many purposes, especially as any white cotton thatmay be woven in does not become 3 5 colored by the dye discharged insoaping.

Colors which are fast may be produced by placing the zinc-mordantedcotton subse quently to mordantin g into a cold-tannin bath or into acold decoction of any other tannincontaining substance, (for example,sumac, divi-divi, quebracho, and the like.) Cotton thus preliminarilymordanted is capable of fixing quantitatively an amount of tannin whichis equivalent to the combined lactate of zinc. This is an advantage notpossessed by the well-known process of mordanting with antimony tannin.

Cotton mordanted with lactate of zinc is also capable of fixing mordantcoloring-matters, that is to say, all the wood dyes, the alizarincoloring-matters and the mordant coloring-matters related thereto (suchas, for example, coerulein, gallein, alizarin-yellow, brilliantalizarin-lolue, &c. in a boiling bath.

As the price of lactate of zinc is considerably less than the price ofthe antimony-tannin mordant, while loss of mordant can be completelyavoided, the cost of mordanting with lactate of zinc can be reduced toabout one-third of the cost heretofore necessary.

Now what I claim and desire to secure by Letters Patent is thefollowing:

The process of dyeing cotton or other vegetable textile fibers whichconsists in mordanting the same with lactate of zinc and subsequentlydyeing the fibers so mordanted.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

ALBERT GANSIVINDT.

Witnesses:

PHIL. REINKING, J OHN JAMES RENDANT.

